Slack-adjuster for railway-brakes.



W. H. SAUVAGE.

SLACK ADJUSTER FOR RAILWAY BRAKES.

APPLICATION FILED MAY15. 1914.

Patented June 15, 1915.

2 SHEETS-SHEET I.

Patented June 15, 1915.

2 SHEETSSHEET 2.

W. H. SAUVAGE.

% 96/ lll/I/E/VTOR 1 I I A ORA/5V8 APPLICATION FILED MAY 15, I914- SLACK ADJUSTER FOR RAILWAY BRAKES.

I was ed.

an A q WILLIAM H. enemies, on new YORK, N. r, AssrcNon are SAUVAGE APPLIANCE company, INC., on new roan, n. a, A conronerron or new roan.

SLACK-ADJUSTER FOR RAILWAY- BRAKES.

specification of Letters Patent. 1 Patented J m g 115, 19115 Application filed may 15, 1914.. Eerial No. 833,883.

To all whom z't may concern: Be it known that I, l/VILLIAM H. SAUVAGE', a citizen of the United sa tes, and a resident of the borough of Manhattan of the city of New York, inthe State of New York, have invented certain new and useful Improvements in Slack Adjusters for Railway- Brakes, of whichthefollowing is a specification, reference being had to the accom panying drawings, forming a part thereof. The general object of this invention is to provide a slack adjuster which may follow freely the movements of the truck bolster and the brake rigging with respect tothe car body. The invention is concerned particularly with the provision of a sleek adjuster in which all of the parts thereof are freely movable with respect to all 'other parts, both in the slack adjuster and in the brake rigging, whereby the entire system is freely flexible and yielding to compensate for the movements of the car truck and bolster with respect to the car body. In realizing the invention the dead lever itself has been made one of the elements of'the slack adjuster. The take-up devices are neither.

mounted on the car body nor on the truck bolster but instead are-carriedby the brake rigging. Not only is a freely flexible and yielding system provided, in which the dead lever forms one of the slack adjuster elements, but the present improvements embody other desirable featureswhich insure.

more efiicient and invariable operation, durabilityv andsimplicity and cheapness of construction.

The invention will now be described more particularlywith reference to the acc0m-' panyingi drawings, in which igure -1 is afv'iew partly in vertical section and partly in side elevation of a portion of a car equipped with the improved slack adjuster. Fig. 2. is-a fragmentary viewona somewhat larger scale of the up bodiment of thepresent invention.

per end of the dead lever shown in Fig, 1 and illustrating particularly the relationship of the holding rod, holding dog and take-up rod: to each other and tothe dead lever. Fig. 3 is a fragmentary view in vertical section taken on the lane indicated by the line 3 '3 of Fig. 2. ig. 4. is a view similar to Fig. 1 showing a somewhat modified em- 5 is a detail view on a larger scale of the s ack adjuster elements shown in Fig. 4. Fig. 6

is a fragmentary view in plan of a portion of the truck bolster, showing particularly the method or" mounting thereon the holding rod and the swiveled abutment for the takeup spring.

llnthe illustrated embodiments, the car body a is shown mounted on a truck bolster b through a body bolster a and king pin 0, the truck bolster in turn being supported through; springs 03 on the" sand plank e, which, as usual, is secured to a portion of the truck frame. On the sand plank e are hingedlymounted through links 7, brake shoes 9 to which are secured the usual brake beams g. The brake shoes 9 may be actuated, as usual, through struts h to which the usual live lever 11 and dead lever is are connected. The lower ends of the live and dead levers may be connected as usual by means of the stiff bottom rod Z, while the upper end of the live lever is connected through the usual pull rod m to any suitable source of power, such as an air cylinder, etc. The construction thusfar described is well known in the art and the corresponding elements thereof may take may move about such a fixed point as a fulcrum, Common practice provides for the anchoring of the upper end of the dead lever, and in the illustrated embodiment .it is proposed that the upper end of the dead lever k shall constitute t e fulcrum for the brake system. Whereas, in known construc tions, this dead lever usually has its upper end connected operatively to the slack adjuster devices,;in-the present embodiment, thedead lever itself becomes one of the elements of the'slack adjuster. Reference to Fig. 3 showsthat the upper end of the dead lever 70 has secured thereto similar holding members. a, as by means of bolts n, and these holding members are formed to receive a holding rack bar 0, the free end of which is anchored to a frame p fixed on the underside ofthecar body (1, preferably adjacent the end sill thereof. The holdingmembers a, it may be noted, are also provided with rod 0.

circular recesses, indicated generally at n, which are opposed to each other to receive the trunnions g of a holding dog g, which normally engages the teeth 0' of the holding By the construction described, it will be evident that the engagement of the holding dog 9 with the holding rack rod 0 maintains the upper end of the dead lever 7a in a relatively stationary position, so that upon application of power to the brake rigging, through the pull rod m, the entire rigging may move about such fixed upper end of the dead lever 'as a fulcrum. .In order to permit the brake rigging to be released entirely, as for the replacing of shoes, etc., the rod 0 is cylindrical in form and arranged within the clamping members n so that it may be rotated freely to disengage the dog 9' from the teeth 0' and thus permit the dead lever is to move freely along said rod. Such a provision is found in a convenient handle 0 fixed to the free end of the rod 0 within easy reach, from the side of the car, of the operator. It is to be noted that the handle 0 is preferably weighted so that upon its release the rod 0 is automatically rotated to bring the teeth 0' in operative relation to the dog 9 so that the next application of the brakes will find the parts in operative positions. Of course, the means for thus returning the rod 0 to its proper position after it is released by the operator, may take widely different forms and the present invention is not to be limited to the precise embodiment illustrated.

The devices for moving the upper end of the dead lever from time to time, as slack occurs in the brake rigging, are found, in the present instance, in a take-up rod r which passes freely through an eye formed in an upward extension z" of the live lever iand also between spring-pressed clutch jaws s mounted within corresponding opposed re-' cesses n? formed in the upper ends of the holding members 7. The rod 1" is maintained in its normal position with respect to the live and dead levers by means of a spiral spring t which, at one end, abuts against a flexible strap 6' of metal or other suitable material, which isconnected yieldingly or flexibly with the truck bolster b, the strap bein maintained in proper position by bolts The end of the anchored strap b against which the spring t seats is' preferably provided with an eye through which passes freely the take-up rod 11. By reason of the flexible connection of this strap with the truck bolster b the strap yields readilywhenever the truck bolster moves up and down and the take-up rod is moved laterally with respect to said bolster. The other end of the spring t abuts against a nut 1" carried on thetake-up rod rt Movement of the take-up rod to the right, as viewed in Fig. 1, under the influence of the springt, is limited by means of a second nut r fastened to it on the opposite side of the flexible strap 7) from the spring t. It is desirable that the live lever z inits normal position should abut against this nut 1 whereby movement of the upper end of the live lever, when the power is removed, is limited or fixed. When the power is applied, the upper end of the live lever 91 moves freely for a distance equal to the normal travel of the brake shoes, as determined by experiment, and during such normal travel, it is to be understood that the takeup-rod 1' remains undisturbed and upon subsequent release of the brakes the parts re turn to their normal position of rest. If however, slack occurs in the system, the upper end of the live lever moves a distance greater than that equal to its normal travel and abuts against a sleeve 1, secured to the end of the take-up rod, continued movement of the upper end of the live lever serving to move the take-up rod to the left as viewed in Fig. 1. This movement of the take-up rod occurs in opposition to the action of the relatively strong spring 29 and a relatively weak spring rso that as soon as the power is released and the upper end of the live lever 2' moves out of engagement with the sleeve 1-, the take-up rod is restored to its normal position under the action of said spring. If for any reason, the spring t does not serve to restore the take-up rod to its normal position, the upper end z" of the live lever will engage the nut r on the takeup rod under the action of the weak spring r, and the rod. be moved to its normal position simultaneously with the normal positioning of the dead lever.

It will .be evident that during the movement of the take-up rod to the left under the action of the live lever, in the manner described, the upper end of the dead lever will be held against movement by reason of the engagement of the holding dog 9 with the rod 0, and the take-up rod will slip freely between the clutch jaws 8. However, when the brakes are released, the clutch'jaws s will grip the rod r with sufficient intensity, under the action of the clutch springs s, as to hold the upper end of the dead lever against movement with respect to the takeup'rod. This clutching actlon results in the upper end of the dead lever being moved to the right, as viewed in Fig. 1, a distance equal to the excess travel of the pull rod m, or, in other words, a distance sufiicient to compensate for the slack in the" brake system. It may be that the movement of the take-up rod r in an axial direction will necessitate a -swiveling movement between it and the dead lever, and to provide for such movement, the clutch jaws s are made cy-' lindrical in form and arranged to turn freely within the clamping members at. From the masses description given it will be seen that the slack is taken up automatically from time to time and the dog 9' is moved along the rack teeth 0 in order that the fulcrum afiorded by the upper end of the dead lever may be changed as required. The certain engagementof the dog 9 with the teeth 0 is assured by recessing the trunnions g of the dog and placing in such recesses suitable torsional springs g which engage operatively with the dog and with the holding members a. In this take-up movement, its range, theoretically, is limited only by the length of the take-up rod and the length of end of the rack bar.

To appreciate fully the advantages of the construction employed consideration must be given to the relationship existing between parts of the truck bolster and the car body during the period of usefulness of the brake system. For the purpose of this consideration it may be pointed out that the sand plank e which is fixed to the journal boxes, and the other parts of the brake riggin g are relatively fixed with. respect to each other, which is to say, that movement imparted to any portion of the brake rigging, as through rough wheels, road bed, etc, will be transmitted to every other portion. The truck bolster I) together with the car body a will have such movements transmitted to them through the springs (Z and increased. Likewise, movement of the car body by rea son of its inertia and by the imposition of external forces, will be transmitted to the truck bolster and bringabout great relative moven' ent between it and the brake rigging. The result is that 'as it may be said, the brake rigging is constantly moving with respect to the truck bolster and car body. The improved slack adjuster system has been designed with special reference to such conditions of use and it has been sought to provide means to insure free flexibility throughout the brake rigging and the slack adjuster elements, whereby the relative movement between the car body and the rigging will he immaterial in so far as the efficient and in variable operation of the slack adjuster is concerned. For instance, the take-up rod 1' and the rack rod 0 follow freely the movements of the dead lever in, the take-up rod follows freely the movements of the live lever; and the flexible abutment strap 6 follows freely the movements of the take-up rod and flexes freely with respect to the truck bolster b. It is this flexibility throughout which is one of the salient features of this invention although, as has now been fully described, an important feature resides in the provision of take-up devices directly on the dead lever.

The modified embodiment of the invention illustrated in Figs. l6 operates generally in the same manner as does the device shown in the first three figures of the drawingsand embraces all of the advantages pointed out with respect thereto, although it will he noted that the holding rod instead of being anchored to the end or draft sill of the car is, in this form, pivotally mounted on the truck bolster Z). When it is: considered that the truck bolster and the car body move as one, in so far as their lateral. movements are concerned, it will be evident that this diffcrence in the point of anchorage of the holding rod 0 becomes immaterial. The dead lever 7c in this construction is substantially the same as the dead lever in the form described, although in this embodiment the holding members 71 support a holding dog Q which is provided with an exposed handle Q to permitits manual release from engagement with the teeth 0 on the rack rod 0. In this embodiment, the'in ner end of the holding rod 0 is mounted hingedly. as on a pintle pin it on the truck bolster I). On the same pin is mounted liingedlv an abutment strap B for the takeup spring I, which abutment strap is disposed in substantially the same r'elation- 1 ship tothe other members of the rigging as in the first described form. Its sole difference in construction resides in the fact that in the second embodiment it is pivotally mounted on the truck bolster, whereas in the first embodiment it is secured fixedly to the truck bolster and flexes with respect thereto by reason of its physical qualities. The operation of the modified. take-up device is substantially the same as that of the first described device save that, when the brakes are to be fully released, the dog Q is tripped manually and the dead lever moved over the holding rod 0, whereas in the first embodiment rotation of the holding rod to disengage the dog from the teeth, is possible. In the second construction, however, all of the advantages pointed out with respect to the first embodiment are retained, in that free flexibility of the entire system is realized and the dead lever itself comprises one of the elements of the slack adjuster.

Modifications in details of construction of some of the elements will suggest themselves to those skilled in the art and rearrangements of such elements Without affecting the basic principle of operatlon may be made, but all such modifications and rearrangements are to be deemed within the scope of this invention provided they fall within the terms and spiritof the appended claims.

I claim as my invention? 1. In an automatic slack adjuster for railway brakes, the combination of the wheel truck and brake system therefor, compriseing a live lever and a dead lever, a bottom rod connection therefor, a take-up rod operatively interposed between the upper ends of the llX'B lever and the dead lever, means carried by the take-uprod and cooperating with the upper end of the live lever to bring about movement of the take-up rod upon travel of the live lever, a spring cooperating with the take-up rod to restore the same to its normal position upon release of the brakes and a clutch to connect the take-up rod with the dead lever during travel of the take-up rod to the normal position.

2. In an automatic slack adjuster for rail.- way brakes, the combination of the wheel truck and brake system therefor, comprising a live lever and a dead lever. a rack bar mounted at one end in a fixed anchorage to the car sills, opposed holding members secured to the upper end of the dead lever and constituting a support for the other end of the rack bar, a holding dog pivotally mounted in said holding members and engaging the teeth on the rack bar, said rack bar being rotatable to disengage the teeth from the holding dog to release the brake system, means cooperating with the rack bar to restore the same to its normal operating position upon release of the rack bar, and means to move the dead lever with respect to the rack bar to shift the fulcrum of the dead lever.

3. In an automatic slack adjuster for railway brakes, the combination of the wheel truck and brake system therefor, comprising a live lever and a dead lever, a bottom rod connection therefor, opposed holding I members carried on the upper end of the dead lever, a take-up rod operatively interposed between the upper ends of the live lever and the dead lever, said take-up rod passing between said holding members, and a spring actuated frictional clutch mounted in said holding members and engaging the take-up rod, whereby movement of the take-up rod tends to move the dead lever.

4;. In an automatic slack adjuster for railway brakes, the combination of the wheel truck and brake system therefor, comprising a live lever and a dead lever, a bottom rod connection therefor, a holding member partially supported by the dead lever and movable freely therewith, a take-up rod operatively interposed between the upper ends of the live lever and the dead lever and freely movable therewith, a spring cooperating with the take-up rod to restore the same to its normal position after excess travel of the upper end of the live lever, and an abutment for said spring carried on the truck bolster and freely movable with respect to the truck bolster and to the takeup rod.

5. In an automatic slack adjuster for railway brakes, the combination of the wheel truck and brake system therefor, comprising a live lever and a dead lever, an automatic take-up device mountedon the brake rigging and including a holding member, said member belng supported in fixed position with respect to the dead lever, a take-up rod operatively interposed between the upper ends of the live lever and the dead lever, a spring cooperating with the take-up rod to restore the same to its normal position after excess travel of the upper end of the live lever and an abutment for said spring freely movable with respect to the truck bolster.

This specification signed and witnessed this 9th day of May A. D. 1914-.

WILLIAM SAUVAGE.

Signed in the presence of- ELLA J. Knncnn, WORTHINGTON CAMPBELL. 

